Prepare butter cream: in same saucepan over low heat, heat milk chocolate, stirring, just until melted; remove saucepan from heat. In large bowl, with mixer at low speed, beat confectioners' sugar, shortening, margarine or butter, milk, and vanilla extract just until mixed. Increase speed to high; beat until light and fluffy, scraping bowl often. Reduce speed to medium; beat in melted milk chocolate.

Place 1 cake layer on cake plate (tuck strips of waxed paper under edge of cake to keep cake plate clean); spread with 1 cup butter cream; top with second cake layer. Spread top and side of cake with remaining butter cream. Chill cake 30 minutes.

Pour chocolate glaze over cake. With metal spatula, spread glaze to completely cover top and side of cake. Chill cake 15 minutes to set glaze. Remove and discard waxed paper.

Garnish cake: With cool hands, carefully peel each leaf from chocolate. Arrange chocolate leaves and cranberries on top of cake to resemble a poinsettia flower. Refrigerate cake if not serving right away. Remove cake from refrigerator 30 minutes before serving to soften chocolate glaze for easier slicing.